Based on case material from the late 1970s and early 1980s from the Institution of Medical Officers of Health covering a Danish county some examples of practical indoor climate problems in day institutions for children are given. Insufficient ventilation of premises is probably the single most important factor in the development of indoor climate problems. An effective cleaning generally improves the indoor air. The study particularly illustrates the administrative and policy perspectives of the decision making process. Those that make decisions on indoor climate problems unfortunately seem to favour a narrow definition of health, i.e., the absence of overt disease; and they are not always aware that the relationship between indoor climate factors and health effects cannot be proven in an absolute sense. Experts on the scientific aspects are needed but their statements are influenced by personal values and their perception of the reasonable balance between health protection and social costs. One of the main factors influencing the indoor climate situation in Danish day institutions for children has been the lack of an adequate regulatory framework; and the central administration and responsible ministers have failed to use the already existing legislative powers to prevent problems. Decision making in cases on the indoor climate of institutions should be accelerated; we cannot wait for proof before taking preventive measures. The indoor air of institutions is a "public good" to the same extent as the ambient air and the responsible authorities have an obligation to regulate accordingly. When building regulations prove insufficient other central authorities must support local decision makers with more specific directions. Testing of building materials, hazard rating and an approval system is needed. Guidelines on indoor climate requirements for public institutions should be developed. In countries with a built-up system of child institutions and a decreasing birth rate it is especially important to improve the already existing institutions. In our regulatory and administrative practice we must restore the balance between the present concern for the health of the adult working population and the insufficient protection of children. We obviously need more research but increased attention should be paid to the administrative and political barriers that prevent improvements of the indoor air.